Mujhe lagta he ke Raj ne jan bujhkar Navin ko nahin mara hain. Yo farz ke khatir majboor tha isliye.LIKE IN SHAKTI DILIP KUMAR KILLED HIS OWN SON FOR THE SAKE OF HIS DUTY. Usi tara raj rote rote navin ko goli mari hogi.YA PHIR ye bhi ho sakta hai ki Navin ne hi Rajveerko majboor kiya use marne ke liye.Kyuin ki yo apne doston ke hath marna chahega jo uski sacchai janta hai na hi un army k hathon jo use traitor samajhke marna chahate hain.REMEMBER LIKR IF FIZA HRITIK ROSHAN COMPELLED KARISHMA TO KILL HIM. agar Raj ne Navin ko jaan bujhkar mara hota to Navin ki aatma kabhi uske saath nahin hota. Woh toh use darata aurkehta k tumne mujhe mara hain.lekin aisa nahin hain. So Rajveer is innocent.
And some members are talking about Rajveer's court martials then for as you know Navin was declared as traitor.So no army officer is court martials for killing a traitor (although he wasn't).
As for Naina she will believe and firstly start hating Raj.Naina bahut foolish hai isliye woh Rajveer pe allegations pe allegations lagayegi but ultimately she will believe him.and Ritu's chaal nakamyab hogi.